Task 7.4 focuses on testing and validating resulting ENVRI-FAIR services at different levels, including individual RI, subdomain, cluster and EOSC. WP7 will support subdomains by testing and validating their specific service developments. Moreover, WP7 will test and validate the resulting ENVRI-FAIR services portfolio at the subdomain, cluster and EOSC level, following the validation guidelines as provided by WP5. In D7.7 the cluster validation activities have been specified and each will test real scientific use cases to check the quality and validate the applicability of (ENVRI-)FAIR services. The EOSC validation activities will test the readiness of the ENVRI-FAIR services at the sub-domain and cluster level for uptake and integration into EOSC together with their possible integrability into the ENVRI service catalogue being developed in WP5. As a result, the test and validation activities will provide feedback to the RI’s and subdomains as to the results of testing and validation and make recommendations to help steer development effectively throughout the project. Additionally, it will provide a report on validation results to WP5 (T5.4) for inclusion in synthesis analysis on the readiness of ENVRI-FAIR services for uptake in EOSC.